Cranes, excavators and the like



July 23, 1963 M. HAGANES CRANES, EXCAVATORS AND THE LIKE Filed Nov. 3, 1961 United States Patent O 3,098,395 CRANES, EXCAVATORS AND THE LIKE Martin Haganes, vre Banegate 43, Stavanger, Norway Fiied Nov. 3, 1961, Ser. No. 150,101 1 Claim. (Cl. 74-105) The present invention relates to cranes, excavators and the like and has particular reference to the means, by which the stem of the crane is rotated in the horizontal plane.y

It is already known to effect said slewing of the main stem of the crane by means of hydraulic cylinders. The known devices have, however, several disadvantages. The turning angle of the crane stem achieved by means of these devices is very small.

It has also been proposed to employ hydraulically operated racks, the teeth of which mesh with the teeth of a gear wheel, iixedly attached to the crane stem. Also in this case the turning angle of the stem is too small to be satisfactory. Besides, these hydraulic rack/ gear wheel-devices have poor tooth engagement and the teeth of the rack and gear wheel will therefore easily be damaged.

The main object of the invention is to provide a most Simple and inexpensive device, free of the above-mentioned disadvantages and capable of effecting a maximal slewing (practically 360) of the crane stem.

According to one feature of the invention there is provided a slewing device, comprising a per se known hydraulic cylinder, the piston rod of which is adapted to turn the crane stem by means of two articulated rods, which are pivotally connected to one another, the one of said articulated rods being mounted in bearings on rigidly fixed brackets, while the other rod is connected with fastening means to the stem of the crane, both articulated rods being connected with the piston rod of the hydraulic cylinder.

According to another feature of the invention, said articulated rod connected with the crane stern is curved in such a way that it will place itself around the crane stern during the turning.

A turning angle of practically 360 may be achieved by means of the device described. First 180 turning is effected, and then the fastening point of said articulated rod on the crane stem is moved to another fastening point situated diametrally opposite the first fastening point (before the turning has begun) and a further turning of 180 is achieved.

The invention will now be described more closely with reference to the accompanying drawing in connection with a preferred embodiment.

FIGURE 1 is a plan view of the device according to the invention, and FIGURE 2 shows the device in side elevation (seen from the left hand side in FIGURE 1).

A hydraulic cylinder 1 with piston rod 2 fitted thereto is mounted on an angle iron 3. Said angle iron 3 may lfor example be attached to the frame of a loading car. The cylinder 1 is at its rear end articulated (5) in channel bearings 4, fixed on the angle iron 5, Other brackets 3,'9853'95 igatented July 23, 1963 ICC 6 on the angle iron serve to articulate (11) a rod 7, whose other ends are articulated to the end of the piston rod 2. Another, curved articulated rod S has one end thereof articulated to the end of the piston rod 2, the other end being attached (or intended to be attached) to a circular disc 10, rigidly fastened to the main crane stem 9, with which it is concentric. Around the circumference of the disc 10 a number of fastening holes is arranged, said holes being referred to as l2 on the drawing. The articulated rod 8 may be attached to either of said holes 12 by means of easily removable pins or the like.

rlfhe two articulated rods or parts 7 and 8 are turned in a horizontal plane by means of the hydraulic cylinder 1, 2 and will be able to turn the crane stem 9 practically without changing the fastening point (12.). After the first turn of 180 has been achieved, the fastening point (12) of the part -8 is moved to another fastening point (i2) diametrically opposite the first fastening point (before the turning has begun) and a further turning of practically 180 may be achieved. The curved form of the articulated rod 8 will also increase the turning angle of the crane stem, as it Will place itself around the stem 9 during turning.

What I claim and desire to secure by letters patent is:

A device for slewing the main stem of a crane or the like, said device comprising a hydraulic cylinder having a piston rod, means pivotally securing one end of said cylinder, a first member having first and second ends, said first end of said first member being pivotally secured near said main stem of said crane, said second end of said first member being pivotally secured to the piston rod of said cylinder, said second end of said first member being disposed between and in front of said means pivotally securing one end of said cylinder and said first end of said first member when said piston rod is retracted within said cylinder, a second member having first and second ends, said first end of said second member being pivotally secured to said second end of said first member, and means fixed to said main stem containing at least two positions disposed on either side of said -main stem, said second end of said second member being selectively and pivotally attached to one of the positions contained in said means fixed to said main stern, Isaid second member curving rearwardly extending about said main stern when the piston rod of said cylinder is extended, said means fixed to said main stem comprising a disk containing apertures spaced about the disk, said second end of said second member being selectively and pivotally secured in said apertures in said disk.

References Cited in the le of this patent UNITED STATES PATENTS 183,061 Locke Oct. 10, 1876 FOREIGN PATENTS 532,775 Italy Sept. l, 1955 ,1,065,150 Germany Sept. 10, 1959 

